Ceramic Coating for Furnaces

Ceramic Coating for Furnaces: Protect Refractory, Cut Fuel Costs, Extend Lining Life

Every hour your furnace runs, the refractory lining degrades. Thermal cycling opens micro-cracks. Slag and flux eat into the surface. Hot spots develop where insulation has thinned. The result is higher fuel bills, unplanned shutdowns, and expensive relines that pull your furnace offline for days.

ITC 100HT is a ceramic coating engineered specifically for furnace environments up to 5000°F (2760°C). Applied directly to refractory brick, castable, or ceramic fiber, it creates a hard, emissive surface that reflects radiant heat back into the chamber — reducing fuel consumption by 20–30% while dramatically slowing refractory wear.

Why Furnace Operators Use ITC 100HT

Fuel Savings That Pay for the Coating in Weeks

ITC 100HT has an emissivity rating above 0.95, meaning it radiates heat back into the furnace chamber instead of letting it soak through the refractory wall. Operators consistently report 20–30% reductions in fuel consumption after coating. For a natural gas furnace running 24/7, that translates to thousands of dollars in savings per month — typically recovering the cost of the coating within the first few weeks of operation.

Extends Refractory Life 2–5x

The coating seals the refractory surface against chemical attack from slag, flux, and oxidation. It bridges micro-cracks before they propagate. Furnace operators who coat new refractory at installation and touch up during scheduled maintenance report lining life extensions of two to five times compared to uncoated refractory — meaning fewer relines, less downtime, and lower total cost of ownership.

Faster Heat-Up, More Uniform Temperature

The high-emissivity surface distributes heat more evenly across the furnace chamber. Hot spots and cold spots are reduced, which improves product quality and shortens heat-up cycles. Foundries and heat treatment shops report reaching operating temperature 15–25% faster after coating, which means more production hours per shift.

Furnace Types Protected by ITC 100HT

ITC 100HT is used in virtually every type of industrial furnace. The coating bonds to any refractory substrate — brick, castable, blanket, or board — and withstands the specific conditions each furnace type demands.

Melting Furnaces

Aluminum melting furnaces, iron cupolas, glass furnaces, and crucible furnaces all benefit from the slag resistance and thermal efficiency ITC 100HT provides. The coating protects against the chemical attack that molten metal and flux inflict on refractory linings, extending the interval between relines.

Heat Treatment Furnaces

Batch and continuous heat treatment furnaces depend on uniform temperature distribution for consistent metallurgical results. ITC 100HT's high emissivity smooths out temperature gradients, improving part quality while reducing the energy needed to maintain setpoint.

Forge Furnaces

Forge furnaces see extreme thermal cycling — rapid heat-ups followed by door openings that shock the refractory with cold air. ITC 100HT's flexibility through thermal cycles prevents the spalling and cracking that uncoated refractory suffers under these conditions.

Boiler Furnaces and Incinerators

High-temperature boiler fireboxes and waste incinerators face both thermal stress and chemical attack from combustion byproducts. The coating acts as a chemical barrier while improving heat transfer efficiency to the boiler tubes or combustion chamber walls.

Ceramic and Pottery Kilns

While we cover kiln-specific applications in detail here, many industrial kilns are functionally furnaces — tunnel kilns, shuttle kilns, and rotary kilns all benefit from ITC 100HT's refractory protection and energy savings.

How to Apply ITC 100HT to a Furnace

Application is straightforward and doesn't require specialized equipment. Most operators apply it themselves during scheduled downtime.

Surface preparation: The refractory surface should be clean and free of loose material, slag buildup, or oil contamination. Wire brushing or scraping is usually sufficient. New refractory should be allowed to cure per the manufacturer's instructions before coating.

Application method: ITC 100HT is a water-based coating that can be brushed, rolled, or sprayed. For furnace interiors, most operators use a brush or paint roller for walls and a sprayer for ceilings and hard-to-reach areas. Apply in two coats, allowing the first coat to dry before applying the second.

Coverage: One gallon covers approximately 20–30 square feet at the recommended thickness. A typical 5-gallon pail handles most small to mid-size furnace chambers.

Curing: Allow the coating to air-dry, then bring the furnace up to operating temperature gradually on the first firing. The coating cures fully during this initial heat-up and bonds permanently to the refractory substrate.

Maintenance: Inspect the coating during scheduled shutdowns. Touch up any areas showing wear — particularly around doors, burner ports, and areas exposed to mechanical abrasion or heavy slag contact. A touch-up coat during annual maintenance keeps the protection continuous.

ITC 100HT vs. Other Furnace Coatings

Most "high temperature" coatings on the market are rated to 1200°F–2000°F — fine for exhaust manifolds and barbecue grills, but nowhere near sufficient for industrial furnace environments. ITC 100HT is rated to 5000°F because it's a true refractory ceramic, not a paint or surface coating in the traditional sense.

The key differences from automotive and consumer-grade high-temperature coatings:

Temperature rating: ITC 100HT handles 5000°F continuous duty. Most competitors max out at 1200°F–2000°F. If your furnace runs above 1500°F, those products will fail.

Emissivity: ITC 100HT's emissivity exceeds 0.95. This is what drives the fuel savings — it's not just a protective barrier, it actively improves the furnace's thermal efficiency by reflecting radiant energy back into the chamber.

Refractory compatibility: ITC 100HT is formulated to bond with refractory materials — brick, castable, ceramic fiber. It's not a general-purpose paint being marketed for furnace use; it was designed for this application from the start.

Proven track record: ITC Coatings has supplied the foundry, ceramics, and heat treatment industries since 1982. The product is specified by refractory engineers and recommended by furnace manufacturers worldwide.

Frequently Asked Questions

How much does it cost to coat a furnace with ITC 100HT?

Material cost depends on furnace size. A 5-gallon pail of ITC 100HT covers approximately 100–150 square feet and is the right quantity for most small to mid-size industrial furnaces. For large installations, we provide volume pricing. Contact us for a quote based on your furnace dimensions.

Can I apply ITC 100HT over existing refractory that's already degraded?

Yes, as long as the refractory is structurally sound. Remove any loose or spalling material, clean the surface, and apply. The coating will seal surface cracks and slow further degradation. For severely damaged refractory, patch the worst areas with castable repair material first, then coat the entire surface.

Does ITC 100HT work on ceramic fiber blanket?

Yes. ITC 100HT bonds well to ceramic fiber blanket and board, hardening the surface against erosion from high-velocity gases while maintaining the insulating properties of the fiber. This is especially valuable in forge furnaces and heat treatment furnaces where ceramic fiber linings are common.

How long does the coating last?

Lifespan depends on furnace conditions — temperature, atmosphere, mechanical wear, and frequency of thermal cycling. In typical industrial service, operators report 1–3 years between recoats in high-wear areas (door jambs, burner zones) and 3–5+ years on walls and ceilings with less direct exposure. Annual touch-ups during scheduled maintenance maximize the coating's protective life.

Is ITC 100HT safe for furnaces processing food-contact materials?

ITC 100HT is an inorganic ceramic coating with no volatile organic compounds after curing. However, specific food-safety certifications depend on your regulatory requirements. Contact us to discuss your application and we'll provide the relevant material safety and composition data.

Get a Quote for Your Furnace

Tell us about your furnace — type, size, operating temperature, and what problems you're trying to solve — and we'll recommend the right product and quantity. Most orders ship within 1–2 business days from our warehouse in San Angelo, Texas.

Call: 325-223-1882
Email: info@itccoatings.com
Online: itccoatings.com